Electromagnetic switch having intermittent operation



Oct 1966 A. R. DE LA ACENA 3,

ELECTROMAGNETIC SWITCH HAVING INTERMITTENT OPERATION Filed Jan. 15, 1964 United States Patent 3,277,412 ELECTROMAGNETIC SWITCH HAVING INTERMITTENT OPERATION Alfonso Romera de la Aceiia, Paseo Reina Cristina 7-5 C, Madrid 7, Spain Filed .Ian. 15, 1964, Ser. No. 337,935 Claims priority, application Spain, Jan. 19, 1963, 284,326 1 Claim. (Cl. 335-138) a small distributor plate which is normally divided into I I two sectors. One of these sectors allows free passage to the current being transmitted by the said brush this constituting ON time whilst the second sector is electrically insulated, and does not permit the passage of current OFF time.

The brush thus operates as a perfect breaker of the circuit of the current to secure intermittent operation, since the rotatory impulses which the said brush receives from the magnetic system which drives it are practically constant, as is also the number of revolutions per minute; and for these reasons the time during which the said brush is in contact with the ON or the OFF sector is like-wise constant.

The magnetic system which transmits the constant impulses to the brush so that the latter, resting on the distributor plate, may transmit or not transmit current to the intermittence circuit, is based on the effect of attraction of a solenoid excited by a cur-rent when there is introduced within it, and oil-centered with respect to the length of the said solenoid, an iron core.

It is known that if an iron core begins to be introduced into the interior of a solenoid through one of its poles, then the said core is attracted towards the other pole by the magnetic field which is created in the interior of the solenoid when an electric current travels through its spirals.

It is likewise known and has been perfectly well demonstrated that the effect of the attraction of a solenoid on an iron core increases progressively as the said core is further introduced into the interior of the said solenoid. This attraction is greatest when the end of the core introduced reaches the transverse section of the center of the solenoid (a very intense magnetic field) and the said effect of attraction diminishes until it becomes eliminated when the ends of the iron core are equidistant from the two ends of the solenoid.

Taking for granted these phenomena of electromagnetic attraction originated by the magnetic field created in the interior of the solenoid by the passage of the electric current, if there is achieved in an automatic and periodic manner, and by means of the system which is being patented, an interruption in the current which excites the spirals of the solenoid once the core has been displaced, but before the total disappearance of the flux which produces the said displacement, and if it is also brought about that the said core is also situated automatically in a position where it may again be attracted, we shall have then achieved the movement of a continuous relay capable of doing a piece of work, the product of a force (the force of the attraction of the solenoid on 3,277,412 Patented Oct. 4, 1966 the core) for an appreciable time governed by the displacement of the core.

If, under these conditions, this work can be applied to the driving of a brush on a distributor plate which transmit-s or does not transmit current, acting as a breaker of a circuit to which lamps are connected, we shall have achieved the desired result which is the subject of the present invention.

In the said drawing:

FIG. 1 is a plan view of an electro-magnetic device carried out in accordance with the present invention.

FIG. 2 is a side elevational view of the same device.

FIGS. 3, 4 and 5 are explanatory views to show the functioning of the device with which we are concerned.

The apparatus which produces intermittence, FIG. 1, may have various dimensions according to the voltage at which it is to operate, the normal voltages for cars being 6-12 and 24 volts.

For the prototype which has been constructed, dimensions have been given on the basis of compactness, such as millimetres high by 55 wide by 50 deep.

The apparatus, FIG. 1, consists of a solenoid of copper wire 1, which can be covered by an iron sheath 1 1 millimetre thick which is provided with various orifices 2 which facilitate the ventilation of the said solenoid. This sheath reinforces the action of attraction of the solenoid.

This solenoid is mounted together with its sheath on a base of Bakelite or fiber 4 and screwed to the said base by means of the lugs 3 which are soldered to'the sheath 1.

The core 5 which is introduced into the solenoid is bimetallic. It consists of magnetically-attracted material such as iron from A to B in FIG. 1, and of brass or some other non-magnetic metal from B to C also in FIG. 1.

The core is supported on, and slides over the ball-bearings 6 and 7 between which the solenoid is situated.

The core terminates in a small weight on the end of its magnetically-attracted section 8 which aids the return of the said core under the current exciting the solenoid ceases to be applied.

The other end of the core or that indicated at C has screwed to it a brass plate 13 by means of a screw 9, and fixed to the said plate is a fiber piece provided with a groove 10 into which groove is introduced a small lever 11 joined to the plate 12 distributing the current.

To the said plate 13 there is joined a rod 14 which on being introduced into the groove of part 15 pulls or pushes the moving part 16 of the element 15 thrusting the said moving part 16 towards the fibre piece 17 intended to open or to leave closed (on returning) the contacts 18 and 19. These metal contacts open or close the circuit because of their being joined to the par-ts of the insulating fibre on which they are mounted 20 and 21 which can turn to a limited extent at points 22 and 23.

The terminals 24 and 25 are those through which the current for driving the electro-magnetic system enters and leaves.

The terminals 26 and 27 are the outlet terminals of the intermittent current which either lights up the lamps situated in the intermittent circuit or else leaves them switched off, according to the positioning of the brush 28 on the distributor plate 29.

The core 5 of the solenoid being formed of two different sections of metal, of which one section, or that shown between A and B, is of magnetically-attractive metal and that section between B and C may be composed of bronze, aluminum or other non-magnetic material. This makes it possible to couple the non-magnetic part of the core to the elements which operate the circuit interruption Without detracting from the force of attraction of the solenoid on the magnetic part A-B of the core. This also makes it possible for the core to travel a relatively long distance which would not occur where wholly magnetic material is' used for the length of the core since the core would remain motionless when the magnetic flux was equal at the magneticpoles A and B. That is to say when the magnetic part of the core was centered in the solenoid.

The magnetic part A-B of the core and the non-magnetic part are welded or otherwise joined to produce an integral core, each of the two halves of the core having completely different characteristics.

The brush 28 is caused to move in the following manner: When the core 5 is elevated due to the attractive action of the solenoid 1, the grooved fibre piece also rises until the lower end of its groove or slot meets the rod 14 which is fixed on the lever or arm 11. This action is shown in FIG. 4.

The lever 11 is joined to the axis of rotation of the brush 28 which makes contact with the distributor plate 12, but because it does not become joined to the plate until the core 5 descends as shown in FIG. 5. When the core descends, as in FIG. 5, the upper end of the groove in the piece 10 touches the rod 14 and then, on the lever 11 uniting with the axis of rotation of the brush 28 which moves on the distributor plate 12, it causes the brush 28 to turn counter-clockwise.

The function of the contacts 18 and 19 is to open or close the circuit to the solenoid which causes the ascension or descent of the core 5. In FIG. 3, the contacts 18 and 19 are in closed position. Since the battery switch 50 is closed the current from the battery 51 passing through the coils of the solenoid 1, passes through the contacts 18 and 19 and returns to the battery. Thus, the current energizes the solenoid and the core 5 ascends as in FIG. 4. On the ascent of the core, the fibre piece 17 becomes introduced between the contacts 19 and 19 and separates them, thus breaking the circuit so that the core descends, its descent being aided by the gravitational effect of the weight 8. When the core descends, the fibre piece 17 also descends and when the contacts 18 and 19 again close, the solenoid is again energized and the core 5 rises to start the cycle just described.

I claim:

An electromagnetic apparatus for causing the intermittent operation of an electric load circuit applicable to vehicle lights comprising:

a solenoid;

a movable core therefor, said core being composed of a part of magnetic material and another part of nonmagnetic material, the parts of the core being united and with the magnetic par-t disposed :beyond the solenoid when the solenoid is d e-energized;

means retracting the magnetic section of the core from within the solenoid when the solenoid is de-energized;

an electrical circuit for supplying electrical energy to said solenoid;

a first switch spaced from the non-magnetic end of said core, said first switch having a pair of opposed contacts normally biased into engagement to close said solenoid circuit;

a first switch operator mounted on the non-magnetic end of said core, said first operator having a portion of dielectric material movable toward said first switch and into contact with said switch toward the end of the stroke of said core to open said contacts and break the electrical cincuit to said solenoid;

a load circuit;

' a step-by-step brush-type switch in said load circuit for intermittently opening and closing said load circuit;

a second switch operator on said non-magnetic end of said core, said second switch operator having an elongated slot therein; and

an actuating arm on said step-by-step switch having a projection freely movable in said slot;

said first switch being open only toward the end of a relatively long stroke of said core and said actuating arm being movable only a relatively short distance by said second switch operator only toward the end of said relatively long stroke of said core.

References Cited by the Examiner UNITED STATES PATENTS 1,306,638 6/1919 Shaw 200-153 1,388,541 7/1921 Woodbury.

1,408,967 3/1922 Arnold 200 1,629,640 5/ 1927 Schachtner.

1,992,945 3/ 1935 Haselton et al.

2,299,498 10/ 1942 Rubinstein et al 20011 2,578,940 12/ 1951 Morris 200- BERNARD A. GILHEANY, Primary Examiner.

T. D. MACBLAIN, Assistant Examiner. 

